The Victron state-of-charge equalizer balances the charge state of two 12 V batteries connected in series or multiple parallel strings of series-connected batteries. When the charging voltage of a 24 V battery system rises above 27 V, the state-of-charge equalizer activates and compares the voltage of the two series-connected batteries. The equalizer draws a current of up to 1 A from the battery or the parallel-connected batteries with the highest voltage. The resulting difference in charging current then ensures that all batteries align to the same charge state. If necessary, multiple state-of-charge equalizers can be connected in parallel. A 48 V battery bank can be balanced using three state-of-charge equalizers.